Did you set Report related system variables for REPORTBEHAVIOR 90 in runtime? Something like

_REPORTOUTPUT = FULLPATH("REPORTOUTPUT.APP")
_REPORTBUILDER = FULLPATH("REPORTBUILDER.APP")
_REPORTPREVIEW = FULLPATH("REPORTPREVIEW.APP")

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>I made a program that execute, in the appropiate line, this command:
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>Modify Report Filename.frx In SCREEN
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>The program show me the report designer and i can modify my report, but when i try to view the result using preview button my program close itself without any message.
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>This behavior is not present if i run my program from VFP (not compiled) or if i write this line before the Modify Report:
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>SET REPORTBEHAVIOR 80
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>Is This a Bug or is another my mistake ?
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